Apparatus for correcting printing plates



L. W. CLAYBOURN APPARATUS FOR CORRECTING PRINTING PLATES March 27, 1928. 1,663,877

Original Filed Jan.4. 1926 2 Sheets-Sheet 1 i Iig l March 27, 1192s. 1,663,877

L. W. CLAYBOURN APPARATUS FOR CORRECTING PRINTING PLATES Original Filed Jan.4. 1926 2 Sheets-Sheet 2 n nnmunuun unuuuuum DDDDUUCIEI Eu DD Patented Mar 27, 1928.

UNITED STATES;

LESLIE w. CLAYBOUBN, or MIL nKE wrsoonsrn.

PATENT OFFICE.

APPARATUS FOR CORRECTING FRINTING PLATES.

Original application filed January 4, 1926, seriai'No. 7a,1ss.- Divided and this application and January'G, 1927. Serial No. 159,389 7 Printing plates as ordinarily made contain variations in the printing surface, some portions being lower and therefore printing lighter, and other portions being higher and therefore printing heavier, and therefore making overlaying 'or underlaying or both necessary before proper printing impressions canbe made. 7

It is the object-of my invention to provide an apparatus for'pressing all parts of the printing portions into the same surface, that is, into the same plane ifthe plate be a flat plate and into the same sector of a cylinder if the plate be a curved plate, by roll ng pressure upon the rear 'face of the printing plate, in order that all printing portions may impress themselves upon a coacting sheet with little or no previous overlaying or underlaying, for minimizing the necessity of make-ready; and, for pressingall portions of the printing surface by rolling pressure into the same surface as determined --by printing pressure.

It is the ob'ect of my invention, further, to provide novel means for exertingroller pressure upon the rear face of the printing plate suflicient to overcome the resistance to local flexure in the printing portions of the printing plate for shaping said printing portions for proper printing; further,-to provide novel means forapplying roller pressure upon the rear face of a printing plate in spaced-apart paths with pressure sufficient to overcome the resistance to local fiexure in the printing portions of the printing surface of said printing plate further, to provide novel means for applying such roller pressure in spaced-apart and alternating paths; and, further, for applying said It is the object of my invention, further,

to provide novel means for compressing a printing plate with rolling pressure which is greater per area of printing surface than the printing pressure per areaapplied to said printing surface.

The invention will be further readilyund'erstood from the following description and claims, and from the drawings, in which latter:

"Fig. 1 represents avertical axial section of-my improved apparatus.

Fig. 2 is'a cross-section of the same, taken in the plane of the line 22 of Fig. 1.

Fig. 3 is a plan view of the same, partly broken away,'with the resistance member removed for better illustration of the pressure members.

I Fig. 4 is a detail view of one of the pres sure members, partlyin section on the line Fig; 5'is a detail view of the same, taken in section on the line 55 of Fig. 4.

Fig' 6 is a plan view of the rear face of a curved printing plate partly corrected by my improved apparatus, and I partly broken away;

Fig. is avertical cross-section, showing an exempl fying apparatus of my invention for correcting curved printing plates, in

which the resistance member is located under the pressure devices.

Fig; 8 is a vertical longitudinal section of Fig. 10 is a horizontal sect-ion, taken in the plane of the line 10-1 O of Fig. 8, show ing the pressure rollers and the mountingstor the same. 1

Fig. 11 is a plan view, partly broken away, stone of the pressure rollers and,

FigzlQ is an enlarged vertical cross-seo-' tion similar to Fig. 7, showing differences in minting surface. f i 1 My improved apparatus is applicable for compressingprinting plates, such as stereotype plates for use in newspaper printing, eleetrotype plates, and-various other. kinds and i s applicable to such plates be f'c'urvedor flat; 7

I have in Figs. 1 and 2 exemplified an apparatus which is particularly adapted for plates whether such of printing plates used in the printing art,

correcting curved stereotype plates, em-

ployed in newspaper printing, which stereotype plates are usually quite tickand of substantially equal dimensions. In Fig. 7 I have exemplified an apparatus employable in correcting curved printing plates, which may be stereotype plates above mentioned, or

curved printing plates such as are used in same, or by being subsequently heated, in order to increase the pliability of the print ing surface, or at other temperatures, and whether such printing surface be of the same material as the bodies of stereotype plates, or be upon a copper or other shell, as is customary in electrotype plates, which latter are provided with a backing of usual backing material, well-known in the art; or the printing plates may be composed of such other'materia-ls as may be customary or desired.

, In my improved apparatus I provide a resistance member to resist pressure upon the printing plate. Such resistance member in Figs. 1 and 2 is exemplified as an arch-piece 21, of suitable pressure resistance material, such as metal, and provided with a resistance surface 22, the resistance portions of which are preferably in the same surface, exemplified as the sector of a cylinder, this surface being preferably the same surface as determined by printing pressures, for the reason that the exactness of correction desired in my improved method is preferably determined by printing pressures, which exactness is ordinarily too refined for observation by the naked eye.

The printing plate in this exemplification .is shown at 25, and has an outer printing surface at 26.

The arch-piece is supported by a frame 27,

and isfirmly 'held thereto in suitable manner,

as by bolts 28. It may be provided with temperature controlling cavities 29. An inlet-pipe 30 and an outlet pipe 31 communicate with said cavities for causing circulation therein of a cooling or heating fluid. The partitions 32 between the cavities may be provided with ports 33 for the purpose.

The printing plate is shown supported by having its respective edges ride on supporting rollers 35, of which there be a suitable number at each side of the recess 36 in the frame, the supporting rollers being respectively suitably rotatably supported on suitable journal bolts 37 threaded into the side walls of the channel. The printing plate may be introduced endwisc into the space in the arch-piece through an opening 38 at one end thereof, and be removed endwise through an opening 39 at theothe'r end thereof.

The printing plate is subjected to rolling pressure applied to the rear face 11 thereof, preferably in spaced-apart paths, which are preferably applied altcrnatingly, with the beginnings 'of the paths preferably, in close relation. These spaced-apart paths are exemplified in Fig. 6 at 42 and a3, the alter nating paths being shown interrupted for better illustration. The paths of one of said sets of paths'preferably fill the spaces be tween the paths of the other. of said sets of paths; Y r

. 1 These pressures are applied across the rear face of the printing plate progressively throughout the area ofthe printing portions 7 of the printing plate, .with pressure sufficient to press all portions ofthe printing surface ofthe' printing plate onto or parallel with said resistance surface, the pressures being preferably sufficient to overcome the resistance to local fiexure in said printing; surface, in order to press all the portions of the printing surface of the printing plate into the same surface, as determined by printing pressures, so that, when said printing plate is put in place in the printing press into coaction with a tympan, suchas a tympan cylinderzor a flat tympan, all resistance portions of which are in the same surface, that said printing surfaces will properly receive the ink from the inking devices of the printing press throughout the printing area thereof, and make a printing impression upon the sheet to be printed, supported by said tympan, without the necessity of or with a minimum amount of under-laying or overlaying for producing a uniform in'ipression throughout the printing area. p

,The rolling pressureupon the printing plate is also preferably sufficient to compress the body of the printing plate into a density at least as great as the density by printing pressure upon the printing plate.

The rolling pressure upon the printing plate is exemplified as accomplished by pressure rollers 51, 52, exemplified as in spacedapart relation by the spaces 53, 54, between the same, the pressurev rollers also being preferably arranged in aplurality of sets roe fill

or rows, the rollers in. the respective sets being in alternating paths. The alternating paths of pressure act upon the printingplate at one operation of the apparatus exemplified.

If desired, one of the spaced-apart sets of rollers may be employed for spaced-apart,

paths of pressure upon the "printing plate, lateral movement between the printing plate and the rollers being then made for coaction between the same pressure rollers and the printing plate in the spaces between the paths of pressure previously applied to the printing plate.

The pressure rollers are exemplified as having protuberances 56 and depressions 57 preferably having sloping walls 58 therebetween. Providing the protuberances, and inversely providing the depressions, aided by the sloping walls when employed, enables pressures to be applied more readily through the thickness of t --e printing plate, and enables more ready transference of such localized pressure from the rear surface of the printing plate to the printing portions of the printing surface of the printing plate,

whereby to press all parts of said printing surface into the same surface, preferably as determined by printing pressures, and with pressure ,suflicie-nt to overcome the resistance to local flexure in the printing portions of the printing plate, in order to reduce all parts of said printing portions to the same surface, also preferably determined by printing pressures.

These protuberances and depressions may be of various forms for obtaining the results desired. They may for instance be-such as more fully shown and described in my Patent No. 1,549,185, for method of correcting printing plates and printing plates produced thereby, dated August 11,1925 The rollers are preferably of hard material, such as steel, although other materials maybe employed. The unevenness of printing surface usual in printing plates, herein described, is also fully shown and described in my aforesaid patent.

The pressure rollers are exemplified as mounted on axles 61, on which they may be rotatable, the axles bein-gsupported in bearings 62, in which they are axially held in suitable manner, the bearings being in yokes -63 of levers 64, pivoted on pivot-rods 65, supported in bearings 66, 67, of a rotary support 68. This rotary support is on ashaft 69, shown fixed thereto by pins 70, the shaft being journaled in bearings 7 1, 72, on the frame. The shaft is suitably driven, as by having a worm-Wheel 73 fixed thereto, a worm 74c. suitably driven, meshing with the worm-wheel.

Pressuremeans for the rollers are exemplified as springs 75, located in sockets '76 in the rotary support. The springs respectively surround plungers 77. Each of the plruigers is provided with a shoulder 78, be-

.tween which and the bottom of the socket the spring is located. The inner end of the retaining lugs 81, with which latches 82 on I l the rotary support coact, these latches being in the form of lugs releasably held to the rotary support in obstructing relation to the lugsj81 by bolts 83, extending through the lugs 82 and threaded intothe rotary support.

The release of any latch permits ready swinging back of the lever held thereby out of the way of the spring, for replacement of the spring, in order that springs of suflicient pressureniay be provided for the printing plates which it is intended to correct, and for other attention to the levers and the parts associated therewith.

The printing plate which it is desired to correct by employment of the apparatus shown in Figs. 1 and 2, is moved axially under the arch-piece 21,- on the supporting rollers 35, against an end gage .84 suitably releasably supported, as by being pivoted by a pivot '85 to the bearing '72. This end gage may be moved into obstructing relation with the plate,-in order to position the plate, and be swung toward the hearing when the plate is to be moved endwise past the bearing. i

' The plate may be preliminarily supported on supporting rollers 86 in line witlrthe supporting rollers 35 on an infeeding bracket '87, :and be supported on outfeeding rollers 88 and an out-feeding bracket :89.

hen the printing plate has been moved into coacting'relation with the arch-piece 21, it being understood that the pressure rollers are then in lowered position, under the operating shaft 69, the operating shaft is caused to rotate for moving the pressure rollers in paths about the inner or rear face of the curved printing plate. so as to press all portionsof the curved printing plate, the paths of pressure moving progressively across the rear face of the printing plate for pressing the printing portions of the printing surface of the printing plate toward the resistance member, and pressing said printing portions into the same plane, and flexing the printing portions of the printing surfacewhich are not in the proper surface into said proper surface for uniform printing el-l'ect of the printingportions of the printing plate, the fact of location of the printing portions in said same surface being preferably determined by printing pressures.

Theaction of the pressure rollers is also preferably to compress the body of the printing plate.v .The compression may produce a density of the body of the printing plate as great as the density due to printing pressure upon said printing plate, in order to resist collapse of the printing plate during the printing, for instance, during the printing of a long run from the same plate.

it is to be understood that after pressure treatment of the printing plate, the rear face of'the printing plate is finished, as by shaving, for removing unevenness caused by indentations of said rear faceby the protuberances on the pressure rollers, and to reduce the printing plate to an even thickness at its printing portions, and other operations are performed on the printing plate, as may be desired, or as more fully shown and described in my aforesaid patent.

' In the form shown in Figs. 1 and 2 there is preferably suflicient space between the printing surface of the printing plate and the resistance face 22 of the resistance member 21,- when the edges of the printing plate ride upon the supporting rollers 35, to prevent abrasion between said printing surface and said resistance face, the pressure rollers pressing said printing surface toward said resistance facewhen acting upon the printing plate.

I have in Fig. 7 exemplified an apparatus in which the arch-piece is shown as a trough 121, and a gage 135 is provided for limiting rotary movement ofthe printing plate. The printing plate 125is, in this instance, preferably introduced into the trough and removed from the trough from the top of the trough. The elements illustrated in this figure, similar to the elements shown in Figs. 1 to 5 are designated by similar reference numerals, raised to the series one hundred. In thisexemplification the idle positions of the pressure rollers are above the rotary support. a

I have in Figs. 8, 9 and 10 exemplifiedmy invention as applied to flat printing plates, rollers similarly mounted being exempilfied. in this instance, however, therotary support is shown as a support 268, mounted on the frame 227, and the resistance member is exemplified as a bed 221, on which the printing plate 225 is supported, with its printing face down. Endwise movement of the printingplate is limited by an end-gage 235.

Relative reciprocating motion between the pressure rollers and the printing plate is accomplished in the present instance by reciprocating the bed or support, which may be accomplished in suitable manner, as by providing the bed with a rack 295, meshed by a pinion 296, on a shaft 269, suitably driven in reverse directions, for feeding or pressure movement and for retracting movement of the bed or support. The-reciprocating bed is slidableinways 297 in the the machine for operation on different thicknesses of printing plates as by providing preferably hardened sheets of various thicknesses between the straight or curved resistance face and the printing surface of the printing plate. v r

The elements in" Figs. 8, 9 and 10, similar to elements shown in Figs. 1 tot, areindicated by similar reference numer-alsraised to the series 200.1 e

The variations in elevations in the print.- ing surface of the printing plate, after being electro-deposited or cast, or both, and

the correction impartediby my improved method, as hereinbefore explained, are exemplifiedin Fig. 12, in which the curved electrotype plate 125 shows lower printing portions 14: 1 and higher printing portions 145, all brought to -the same printing level 1 16 by my improved apparatus. 1 v

I do not herein claim the method of correcting printing plates herein shownnand described," having -shown, described and claimed thesame-in an application forLetters Patent heretofore filed 'by me in the United States Patent Oliice January'1926,

as Serial No. 79,168, for improvements in method ofcorrecting printing plates and apparatus therefor, of which .the'present application is a division. 1

Having thus fully described my invention, what Iclaim as new, and'des'ire to secure by Letters Patent, is: V 1. In an apparatus for-correcting printing plates, the combination of a resistance member provided with a resistance surface for the printing surface of a a printing plate, compression rollers arranged in sets, the compression rollers whereof are spaced in endwise rela tion, with the rollers of said respective'sets operating between the paths of compression of the rollers of the other of said sets, arranged whereby to overcome the resistance to local flexure in saidprinting surface, and means causing progressive movement between said compression rollers and said resistance surface for coactive movement between said compression rollers and the rear surface of said-printing plate along said rear surface.

2. In an apparatus for correcting printing plates, the combination of a resistance member for the printing surface of a printing plate, a plurality of sets of spaced-apart pressure rollers coacting with the rear face flexure in said printing surface, and means causing progress1ve' movement between said rollers and said rear face along said rear face.

3. In an apparatus for correcting printing plates, the combination of a resistance memher for the printing surface of a printing plate, a plurality of sets of spaced-apart pressure rollers coacting with the rear face of said printing plate, said pressure rollers provided with compression protuberances, means supporting the pressure rollers of the respective sets in the spaces between the paths of the rollers of the others of said sets for closely associating the impressions by said protuberances in said rear face, pres sure means to cause pressure between said rollers and said rear face to overcomerresistance to local flexure in said printing surface, and means causing progressive movement between said rollers and said rear face along said rear face.

4. In an. apparatus for correcting curved printing plates, the combination of a resistance member having a curved resistance sur? face for the curved printing surface of a curved printing plate, a rotary support arranged to rotate within the curvature of said curved resistance surface, oppositely disposed levers pivoted in staggered relation on said support, spaced-apart rollers arranged in staggered relation on said levers coacting with the rear curved face of said printing plate, and means causing compressive action by said rollers upon said rear curved surface to overcome the resistance to local fiexure spective rows pivoted in staggered relation to said rotary support, a row of spacedapart compression rollers in the levers of said respective rows of levers, the compression rollers of each of said rows arranged in the spaces between the paths of the compression rollers of the other of said rows, and means causing compressive action of said rollers on the rear curved face of said printing plate to overcome the resistance to local flexure in said printing surface.

6. In an apparatus for correcting curved printing plates, the combination of a curved resistance member having a curved resistance face for the printing surface of the printing plate, a plurality of sets of spaced-apart pressure rollers coacting with the curved rear face of said printing plate, means supporting the pressure rollers of the respective sets in the spaces between the paths of the rollers of the others of said sets, pressure means to causepressure between said rollers and said rear face to overcome resistance to local flexure insaidprinting surface, and

ers provided with compression protuberances, means supporting the pressure rollers of the c respective sets in the spaces between the paths of the rollers of the others of said sets I I for closely associating the impressions by' said protuberances in said rear face, pressure means to cause pressure between said rollers and said rear face to overcome resistance to local fiexure'in said printing sur face, and means causing progressive movement between said rollers and said rear face along said rear face.

In testimony whereof, I have hereunto signed my name.

LESLIE W. GLAYBOURN. 

